Drying cabinet comprising a cleaning device

ABSTRACT

A drying system includes a drying cabinet having a plurality of horizontally heating plates, and a cleaning device which can be inserted into the interior of the cabinet. The cleaning device includes a carrier supported on the interior bottom of the drying cabinet and having a duct and a plurality of horizontal support arms with a cavity being fastened to the carrier, each cavity communicating with the duct. A support arm is arranged above each of the heating plates. Each of the support arms is outfitted with a spray arm which is rotatable horizontally around an axis A. Each spray arm has a quantity of nozzles. In addition, the carrier and the drying cabinet have means through which a cleaning agent can be supplied to the duct.

The invention is directed to a drying cabinet of the type indicated inthe preamble of claim 1.

Drying cabinets of the kind mentioned above are used, for example, fordrying pharmaceutical or chemical products or foods such as milk,proteins, soups, fruits, vegetables and the like. Drying is oftencarried out under vacuum and the drying cabinets are designedaccordingly.

These drying cabinets become soiled in operation and this dirt must beeliminated by cleaning. Formerly, this was performed manually; butguidelines have existed for some time which can only be met whencleaning devices are provided whose operation can be documented.

A drying cabinet of the type indicated in the preamble of claim 1 isknown from DE-C1-198 08 408. Its upper wall has a pipe connection piecewhich can be closed in a vacuum-tight manner, a cleaning device beinginsertable into the interior of the drying cabinet through this pipeconnection piece. This cleaning device, which is driven by a motor, hasjets or nozzles through which the cleaning fluid can be sprayed into theindividual tiers of the drying cabinet. The jet of cleaning agent exitsthe nozzle horizontally. Because the nozzle is swivelable horizontally,the jet can also reach the corners of the interior of the dryingcabinet.

A drying cabinet which is outfitted with a stationary cleaning device isknown from DE-A1-100 28 895. Pipes arranged on both sides of the shelveshave a plurality of nozzles through which the cleaning agent can besprayed onto the individual shelves.

DE-C1-36 09 115 discloses a baking oven having a device for supplyingexpanded wet steam. Further, there is a rinsing device by means of whichsuds can be introduced into the baking chamber through spray nozzles.

U.S. Pat. No. 4,732,172 discloses a washing device for transfer cartsand EP-A2-1 055 462 discloses a device for cleaning germination decks.Further, a drying device is known from U.S. Pat. No. 6,158,146.

It is the object of the invention to provide a drying cabinet with acleaning device whose cleaning action is further improved compared tothe previously known prior art.

This object is met according to the invention through the features ofclaim 1. Advantageous further developments of the invention areindicated in the dependent claims.

Embodiment examples of the invention are described more fully in thefollowing with reference to the drawings.

FIG. 1 shows a vertical section through a drying cabinet with a view ofa cleaning device;

FIG. 2 shows a horizontal section with a top view of the cleaningdevice;

FIG. 3 shows details of a spray arm;

FIG. 4 shows a device for transporting the cleaning device;

FIG. 5 shows a drying cabinet with integrated cleaning device; and

FIG. 6 shows a variant of a spray arm.

In FIG. 1, which shows a vertical section through a drying cabinet witha view of a cleaning device, a drying cabinet in its entirety isdesignated by 1. This drying cabinet 1 comprises a housing cube 2 whichis open on one side and which can be closed on the open side by a door3. When the drying cabinet 1 is designed as a vacuum drying cabinet, aseal, not shown, is fastened to the door 3. The interior of the dryingcabinet 1 is designated by 4. This interior 4 is subdivided by heatingplates 5 which are designed as shelves upon which product trays 6 can beplaced. These product trays 6 are removable. Therefore, they can becleaned outside of the drying cabinet 1 in a particularly efficientmanner. Only one of the product trays 6, that on the topmost heatingplate 5, is shown. All product trays 6 are removed from the dryingcabinet 1 when cleaning work is performed on the drying cabinet 1; forthis reason, the one product tray 6 is indicated in dashed lines to showits position. The bottom of the drying cabinet 1 can also contain aheating plate 5.

A cleaning device 10 is inserted into the drying cabinet 1. Thiscleaning device 10 is either arranged in a stationary manner in thedrying cabinet 1 or can advantageously be inserted into and then removedfrom the drying cabinet 1. This is shown again in detail. When thecleaning device 10 is removable, it can be used successively for aplurality of drying cabinets 1. This economizes on capital investmentbecause only one cleaning device 10 need be procured for a large numberof drying cabinets.

The cleaning device 10 comprises a support or carrier 11 to which isattached a plurality of horizontal support arms 12. The quantity ofsupport arms 12 is equal to the quantity of intermediate spaces betweenthe top of the interior space 4, the heating plates 5 and the bottom ofthe interior space 4 of the drying cabinet 1. A spray arm 13 whichrotates around the vertical axis A is rotatably arranged at each of thesupport arms 12. Every spray arm 13 is outfitted with a quantity ofnozzles 14. These nozzles 14 are so constructed in a known manner thatthe liquid jet exits at an inclination to the longitudinal axis of thespray arm 13 so that the spray arm 13 is set in rotation about the axisA by the recoil of the spray jet. Accordingly, a motorized drive unit ofthe spray arm 13 can be dispensed with. The carrier 11 has a duct 15 inits interior through which the cleaning agent reaches the support arms12 and then, through cavities 16 in the support arms 12, arrives at thespray arms 13.

In the present embodiment example, the carrier 11 is supported on theinterior bottom of the drying cabinet 1. It can be fixedly mountedthereon or can simply rest upon this interior base so that it can beremoved. Other solutions are possible within the framework of theinvention; for example, supporting on the heating plates 5, e.g., thetopmost heating plate 5, or supporting in guide rails at the two sidewalls of the interior space 4 of the drying cabinet 1.

The carrier 11 has an opening 20 through which the cleaning agent canenter into the duct 15. The cleaning agent which can be supplied in thisway then travels through the duct 15 to the cavities 16 of theindividual support arms 12 and arrives at the interior of the individualspray arms 13, through whose nozzles 14 it can be sprayed into theinterior 4 of the drying cabinet 1.

A closable bore hole in the bottom of the drying cabinet 1 through whichthe cleaning agent can flow is known from DE-C1-198 08 408 but is notshown.

FIG. 2 shows a horizontal section through the drying cabinet 1 with atop view of the cleaning device 10. Also shown is a top view of asupport arm 12 which is connected to the carrier 11 and a spray arm 13which is fastened to the support arm 12 so as to be rotatable around theaxis A. The spray arm 13 has nozzles 14. On one of the legs of the sprayarm 13, the nozzles 14 lie on top and so are indicated in FIG. 2 bysolid lines, whereas on the other leg they are arranged on the undersideand are therefore shown in dashed lines. The rotation of the spray arm13 around the axis A is indicated by an arrow.

The opening 20 in the carrier 11 is also shown. A connection piece 21adjoins this opening 20 and is connected at the other side to a pipeguide-through 22 which penetrates the side wall of the housing cube 2 ofthe drying cabinet 1. Couplings at this pipe guide-through 22 by whichthe connection piece 21 can easily be connected to the pipeguide-through 22 and by which this pipe guide-through can easily beconnected to a connection line, not shown, for the cleaning agent arenot shown because the known prior art contains usable solutions forthis. The drawings also do not show means by which the pipeguide-through 22 can be closed in a tight manner when the cleaningdevice 10 has been removed from the drying cabinet 1.

FIG. 3 shows an advantageous construction of a spray arm 13 with itsnozzles 14. Also shown is a flow duct 24 which communicates with thecavity 16 of the support arm 12. Accordingly, the cleaning agent canflow from the cavity 16 into the flow duct 24 and can then enter theinterior 4 (FIG. 1) of the drying cabinet 1 through the individualnozzles 14.

Nozzles 14 which spray approximately horizontally are advantageouslyprovided at the radial ends of the spray arm 13, which serves todistribute the cleaning agent in the interior 4 in an optimal manner.Another nozzle 14 in the middle portion 25 of the spray arm 13 alsoserves this purpose. The step whereby the two legs of the spray arm 13are arranged so as to be offset in height also serves for optimaldistribution of the cleaning agent. The leg having nozzles 14 sprayingupward is arranged farther down, while the leg having nozzles 14spraying downward is arranged farther up.

FIG. 4 shows the drying cabinet 1 with open door 3, not shown, and adevice for transporting the cleaning device 10. Drying cabinets 1 forthe chemical, pharmaceutical and foodstuffs industries can havesubstantial dimensions, e.g., approximately 2×2×2 m. The cleaning device10 has corresponding dimensions and, therefore, considerable weight. Atransporting device 40 of this kind is advantageous for enabling oneperson to cope with inserting the cleaning device 10 into and removingit from the drying cabinet 1. The transporting device 40 is movable bymeans of wheels 41 on the surface 42 upon which the drying cabinet 1stands. The transporting device 4 has coupling means 43 by which thecleaning device 10 can be connected to the transporting device 40 in africtional engagement.

It can be seen from FIGS. 1 and 2 that owing to the shape of thecleaning device 10 it is not possible to remove the product trays 6 fromor insert then into the drying cabinet 1 when the cleaning device 10 isinserted in the drying cabinet 1. However, this is only true when theproduct trays 6 are so dimensioned that they correspond approximately tothe width and depth of the heating plates 5. With smaller product trays6, this problem does not occur. Accordingly, before the drying cabinet 1can be loaded or unloaded when using product trays 6 of this size, thecleaning device 10 must be removed from the drying cabinet 1. Thetransporting device 40 which is shown schematically advantageouslyserves for this purpose. The transporting device 40 is also applied whena cleaning device 10 is used for a plurality of drying cabinets 1successively as was already mentioned above.

Further, in contrast to FIGS. 1 and 2, FIG. 4 shows a differentplacement of the connection of the cleaning device 10 for supplying withcleaning agent. In this instance, the pipe guide-through 22 is arrangedin the rear wall of the drying cabinet 1 and the opening 20 is locatedat a front side of the carrier 11 facing the pipe guide-through 22. Theopening 20 and the pipe guide-through 22 can be constructed as aquick-coupling, so that the cleaning device 10 is automatically coupledto a line for the cleaning agent when the cleaning device 10 is movedinto the drying cabinet 1.

If the cleaning device 10 is to be an integral component part of thedrying cabinet 1, that is, not removable, the carrier 11 isadvantageously designed in such a way that it does not impede insertionand removal of large product trays 6. An advantageous construction ofthis kind is shown in FIG. 5.

In this case, the carrier 11 is arranged in one of the corners of thedrying cabinet 1. The support arms 12 which are fastened to the carrier11 are swivelable. Accordingly, the carrier 11 with the support arms 12rigidly fastened thereto can be rotatable around its own axis or thesupport arms 12 can be swivelable around the carrier 11. The idleposition of the support arms 12 with the spray arm 13 fastened theretois indicated by solid lines in FIG. 5; the position occupied whencarrying out cleaning is shown by dashed lines. In this case, thesupport arm 12 projects diagonally into the interior 4 of the dryingcabinet 1 toward its center.

A variant of a spray arm 13 is shown in a schematic top view in FIG. 6.As in the embodiment example in FIG. 3, the nozzles 14 of one arm spraydownward and those of the other arm spray upward. The nozzles 14 at theradial ends of the spray arm 13 do not spray in radial direction, butrather at an appreciable inclination to the longitudinal axis of thespray arm 13, which produces the force for the rotation of the spray arm13 around its axis of rotation A as a result of the recoil of the sprayjet.

Further constructions are possible within the framework of the generalidea of the invention. In sum, a drying cabinet (1) with a cleaningdevice (10) having an improved cleaning action is provided by means ofthe invention and its variants.

1-9. (canceled)
 10. A drying system comprising a drying cabinet and acleaning device, the drying cabinet comprising an interior having a top,a bottom, and a plurality of heating plates arranged horizontallybetween the top and the bottom to form a plurality of intermediatespaces, the drying device comprising: a vertical carrier having a duct;a plurality of support arms extending horizontally from the carrier intorespective said intermediate spaces, each support arm having a cavitywhich communicates with the duct; and a plurality of spray armsrotatably mounted on respective said support arms, each said spray armhaving a plurality of nozzles connected to a respective said cavity. 11.A drying system as in claim 10 wherein at least one of said nozzles oneach said spray arm is mounted to spray liquid at an acute angle withrespect to a horizontal plane, thereby caused said spray arm to rotatewhen water is being sprayed.
 12. A drying system as in claim 10 whereinthe carrier is fixed in the drying cabinet.
 13. A drying system as inclaim 12 wherein the carrier is mounted in a corner of the dryingcabinet.
 14. A drying system as in claim 10 wherein the carrier isremovable from the drying cabinet.
 15. A drying system as in claim 14further comprising a transporting device having couplings which engagethe carrier.
 16. A drying system as in claim 10 wherein each said sprayarm has a first leg having nozzles which spray upward and a second leghaving nozzles which spray downward, said second leg being radiallyopposite and above said first leg.
 17. A drying system as in claim 10wherein each said spray arm has radially opposed ends, each said endhaving a nozzle which sprays substantially horizontally.
 18. A dryingsystem as in claim 10 further comprising a nozzle arranged on the axisof rotation of the spray arm.
 19. A drying system as in claim 10 whereinthe spray arms are mounted for rotation about a common vertical axis.